Belossum
Being caught in Belossum's sleeping spell can become a living nightmare. As soon as your character wakes up, they'll often be instantly put back to sleep by the fumes. In the moment where you're awake, you can roll away (R + left or right) to escape this unpleasant dream.

Celebi*
This harmless yet graceful creature doesn't attack anyone. Instead, he quickly floats upward and disappears as quickly as he came. Celebi sightings are few and far between, and it only happens after you've unlocked everything (All Characters plus the Sound Test, Random Stage select, and Score Display). Being the player that released Celebi from a Pokéball will net you 8,000 bonus points.

Clefairy
This helpless looking little pink guy might look harmless, but he's certainly far from it. When Clefairy appears, he'll perform one of several different attacks, some of which are much more devastating than others. The best bet is to stay clear of him, because you never know what he's going to dish out.

Chansey
This egg-laying Pokémon will start tossing eggs around the arena whenever she appears. The eggs themselves can be picked up by players, and inside you'll find items and sometimes health.

Entei *
Entei is among the more infrequent monsters. But as is the case with other creatures who are seldom seen, when Entei does appear, the attack can be devastating. This monster will create a huge fire inferno that stretches upwards, successfully torching anyone who's unfortunate enough to be in the way. Throw another Pikachu on the BBQ...

Goldeen
A Pokémon character that seems completely and totally useless... After escaping from a Pokéball, Goldeen will helplessly flop around like a fish out of water. Goldeen appearing seems to have no purpose at all, and you don't even receive bonus points for getting this odd creature...

Lugia*
Another one of the big boys. You'll have a lot of warning before having to deal with an attack from Lugia, because he'll appear, and flap his wings as he travels to the background of the stage. From here, he'll unleash a spinning water attack that will hit players directly in front of him. So as is the key with other big monsters, just keep to either side when you see him appear.

Marill
Not nearly as strong or dangerous as some of the other monsters covered on this page. Marill stays on the ground, and run in a straight line while hitting players in his way. He's a perfect distraction though, because while other players might be dealing with the annoying hits from Marill, you can line them up for a much more vicious attack of your own.

Mew *
A fairly infrequent sight for Melee players. Although he's one of the few characters that don't attack, anyone who happens to find Mew in a Pokéball will be rewarded with 10,000 points. He offers only a faint "Meow", then floats upwards in a magical bubble. You won't even stand a chance of seeing Mew until you unlock all of the game's characters.

Suicune *
This rather exotic Pokémon will unleash a vicious tropical storm when it appears. Water will continuously swirl around Suicune, trapping players in a circular wash cycle. Players caught up in Suicune's attack will be heavily damaged, but will come out shiny just like clean plates from the dishwasher...

Raiku *
Similar to Suicune mentioned above, Raiku traps players in his vicinity. But unlike Suicune's clean cycle, Raiku will send volts of electricity into the bodies of unfortunate players. Getting repeatedly zapped by Raiku's electrical charges isn't a pleasant experience, so take measures to avoid the electrical storm before it starts.

Togepi
Another Pokémon like Clefairy, who has a variety of different attacks. Togepi's most devastating trick is a bright explosion that causes the lights to go out for a short period of time. In the dark, you'll have no idea where you are, or how close it is to the nearest ledge. The best move, is not to do anything foolish when you can't see.

Unown
The Unown attack in a giant pack when they are released. Each one of them does very little damage, but being hit with the entire swarm is enough to make you suffer consecutive hits. Also, when a player is being harassed by these flying foes, they can become partially immobilized in the air. This provides an excellent opportunity to dish out damage to a distracted victim.

Venusaur
When Venusaur escapes from a Pokéball, he remains stationary and angrily stomps the ground. This constant pounding of his thundering feet is enough to shake things up, and any players within his range will be thrown around in the air. Keep away from his mad rampage, while trying to grab your opponent and toss 'em in.